Re: [hibernate-dev] Missing transaction hangs the testsuite

Process != test. Process here == connection. You have multiple. On Fri, Jul 17, 2015, 11:12 AM Sanne Grinovero <sanne(a)hibernate.org&gt; wrote: > On 17 July 2015 at 16:25, Steve Ebersole <steve(a)hibernate.org&gt; wrote: > > It would seem that this is a regression with ORM, I agree. However, we > do > > not know how recent of a regression. And that is the problem. We have > no > > idea how far back to look. Because the ORM CI jobs against MySQL, > > PostrgreSQL, Oracle, etc have not been running for many months. IIRC > even > > when they were running on the old CI servers we had problems with those > jobs > > that were not looked at for some time. > > Sure, same problem here: not run these tests for months, and you're > right I could do a quick check on a slightly older branch which is > using ORM 4.3 and I have the same problem. > > > As far as what you see, I am not convinced it is what you think it is in > > terms of auto-commit for queries run outside of a transaction. This > part > > has not changed in 5.0. Assuming you are using the "built in Connection > > pool", there is a setting that controls the auto-commit mode of the > > connections we create (hibernate.connection.autocommit). That setting > has > > always been there, and it has always defaulted to false. This has not > > changed. In fact the same exact code is used in 4.3 and 5.0 for > creating > > these Connections: > > org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator. > The > > autoCommit value in there comes from the setting I just mentioned. The > > logical outcome is the same even before 4.3, just that it was done > > differently. So bottom line, if you are not seeing auto-commit on these > > Connections now, you never were. Now it is possible that their are some > > ancillary changes that cause the lack of auto-commit to now be an issue > > where it was not before. So first, I'd need to know whether the > Connection > > here is auto-commit or is not. From there we can start drilling down on > > what might be a cause. But keep in mind too, that with hangs and > deadlocks > > the process that hangs is often not the culprit; often it is the > previous > > process that is holding locks that is the culprit. > > I understand, but in this specific case I can reproduce the issue by > running a single test. > Also that psql SQL I shared clearly shows which statement is causing it > to hang, > and I could fix the test by just wrapping that statement in a transaction. > > > > > My case is actually different, at least on the surface. Mine happens on > > dropping tables after the test is complete (for MySQL anyway). Which > got me > > to looking at schema export and friends and how they handle connections. > > They handle connections quite differently. Again the same as they used > to, > > but I mean very different from how sessions manage connections. In > schema > > export the connections are always set to auto-commit mode at the start > of > > processing. Then they never do anything with auto-commit afterwards. > I am > > not sure this is right. > > Actually it sounds like you're having the same problem. I debugged the > PosgreSQL tests first, but I had the same on MySQL (as in the > stacktrace I shared), > and the test also hangs on schema drop. > The problem is that the schema can't be dropped because a previous > statement - from a session which is now correctly closed - is still > holding locks. > > Thanks, > Sanne > > > > > > > > > > > On Fri, Jul 17, 2015 at 3:51 AM Sanne Grinovero <sanne(a)hibernate.org&gt; > wrote: > >> > >> Thanks Steve, I wasn't sure if I had found a problem. > >> Still, it looks like the Hibernate Search tests are not benefiting > >> from auto-commit, or I wouldn't have this problem right? Our testing > >> configuration properties have been the same for years and I'm just > >> re-enabling tests which haven't been run for a while, so I suspect > >> something changed in ORM. > >> > >> I think I'd expect Hibernate ORM to automatically enable auto-commit > >> on operations not running within a transaction, to make sure all locks > >> are released when the Session is closed. > >> > >> Thanks, > >> Sanne > >> > >> On 17 July 2015 at 00:14, Steve Ebersole <steve(a)hibernate.org&gt; wrote: > >> > For what it is worth, I am running into the same problems on MySQL > for > >> > the > >> > ORM tests in terms of blocks on dropping tables. PGSQL at least > >> > finishes, > >> > although I run into 55 errors which I still need to triage. > >> > > >> > On Thu, Jul 16, 2015 at 5:59 PM Steve Ebersole <steve(a)hibernate.org&gt; > >> > wrote: > >> >> > >> >> There is really nothing to improve. What would you suggest as an > >> >> improvement? I mean from a ORM perspective, we have an ato-commit > >> >> Connection (presumably) and run a query. How on earth would we > know to > >> >> expect that the database is holding locks for that? > >> >> > >> >> As far as "requiring transactions" I have tried to fly that plane > >> >> multiple > >> >> times in the past. I think it is absolutely ridiculous to allow > these > >> >> auto-commit use cases. In fact I personally wanted to take it to > the > >> >> more > >> >> extreme case of always using JTA and simply mimicking "single > resource > >> >> JTA > >> >> transactions" internally in the "JDBC transaction" case. Gavin and > I > >> >> both > >> >> did in fact. But we got a lot of push back. > >> >> > >> >> So I am not sure exactly what the improvement here might be. What > is > >> >> it > >> >> you were thinking specifically? > >> >> > >> >> On Thu, Jul 16, 2015 at 5:36 PM Sanne Grinovero < > sanne(a)hibernate.org&gt; > >> > >> >> wrote: > >> >>> > >> >>> I finally got to re-enable MariaDB and PostgreSQL based tests for > >> >>> Hibernate Search - which has been running on H2 only for some > months - > >> >>> and had to debug a case of a single test hanging for a long time. > >> >>> > >> >>> Essentially it would block - for hours - on the > SessionFactory#close() > >> >>> method, attempting to drop the database schema with the following > >> >>> statement: > >> >>> > alter table AncientBook_alternativeTitles drop constraint > >> >>> FKn8hhkmhof1mdgc4oi77ccq989 > >> >>> > >> >>> Dumping threads I would get a very similar stack trace on both > >> >>> databases; initially I thought someone had copy/pasted a socket > >> >>> handling bug from one JDBC driver to the other ;-) > >> >>> > >> >>> The PostgreSQL testsuite hanging: > >> >>> > >> >>> "main" prio=10 tid=0x00007f0f40009000 nid=0x5f7c runnable > >> >>> [0x00007f0f48956000] > >> >>> java.lang.Thread.State: RUNNABLE > >> >>> at java.net.SocketInputStream.socketRead0(Native Method) > >> >>> at java.net.SocketInputStream.read(SocketInputStream.java:152) > >> >>> at java.net.SocketInputStream.read(SocketInputStream.java:122) > >> >>> at > >> >>> > >> >>> > org.postgresql.core.VisibleBufferedInputStream.readMore(VisibleBufferedInputStream.java:145) > >> >>> at > >> >>> > >> >>> > org.postgresql.core.VisibleBufferedInputStream.ensureBytes(VisibleBufferedInputStream.java:114) > >> >>> at > >> >>> > >> >>> > org.postgresql.core.VisibleBufferedInputStream.read(VisibleBufferedInputStream.java:73) > >> >>> at org.postgresql.core.PGStream.ReceiveChar(PGStream.java:274) > >> >>> at > >> >>> > >> >>> > org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1660) > >> >>> at > >> >>> > >> >>> > org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:257) > >> >>> - locked <0x00000007c11e3860> (a > >> >>> org.postgresql.core.v3.QueryExecutorImpl) > >> >>> at > >> >>> > >> >>> > org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:500) > >> >>> at > >> >>> > >> >>> > org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:374) > >> >>> at > >> >>> > >> >>> > org.postgresql.jdbc2.AbstractJdbc2Statement.executeUpdate(AbstractJdbc2Statement.java:302) > >> >>> at > >> >>> > >> >>> > org.hibernate.tool.hbm2ddl.DatabaseExporter.export(DatabaseExporter.java:47) > >> >>> at > >> >>> > org.hibernate.tool.hbm2ddl.SchemaExport.perform(SchemaExport.java:476) > >> >>> at > >> >>> > org.hibernate.tool.hbm2ddl.SchemaExport.execute(SchemaExport.java:430) > >> >>> at > org.hibernate.tool.hbm2ddl.SchemaExport.drop(SchemaExport.java:375) > >> >>> at > org.hibernate.tool.hbm2ddl.SchemaExport.drop(SchemaExport.java:371) > >> >>> at > >> >>> > >> >>> > org.hibernate.internal.SessionFactoryImpl.close(SessionFactoryImpl.java:1069) > >> >>> at > >> >>> > >> >>> > org.hibernate.search.test.util.FullTextSessionBuilder.close(FullTextSessionBuilder.java:149) > >> >>> at > >> >>> > >> >>> > org.hibernate.search.test.util.FullTextSessionBuilder$1.evaluate(FullTextSessionBuilder.java:248) > >> >>> at org.junit.rules.RunRules.evaluate(RunRules.java:20) > >> >>> at org.junit.runners.ParentRunner.run(ParentRunner.java:309) > >> >>> at > >> >>> > >> >>> > org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:264) > >> >>> at > >> >>> > >> >>> > org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:153) > >> >>> at > >> >>> > >> >>> > org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:124) > >> >>> at > >> >>> > >> >>> > org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:200) > >> >>> at > >> >>> > >> >>> > org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:153) > >> >>> at > >> >>> > >> >>> > org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:103) > >> >>> > >> >>> The MariaDB testsuite hanging: > >> >>> > >> >>> "main" prio=10 tid=0x00007f8ca0009000 nid=0x4043 runnable > >> >>> [0x00007f8ca5f5c000] > >> >>> java.lang.Thread.State: RUNNABLE > >> >>> at java.net.SocketInputStream.socketRead0(Native Method) > >> >>> at java.net.SocketInputStream.read(SocketInputStream.java:152) > >> >>> at java.net.SocketInputStream.read(SocketInputStream.java:122) > >> >>> at > >> >>> > >> >>> > com.mysql.jdbc.util.ReadAheadInputStream.fill(ReadAheadInputStream.java:114) > >> >>> at > >> >>> > >> >>> > com.mysql.jdbc.util.ReadAheadInputStream.readFromUnderlyingStreamIfNecessary(ReadAheadInputStream.java:161) > >> >>> at > >> >>> > >> >>> > com.mysql.jdbc.util.ReadAheadInputStream.read(ReadAheadInputStream.java:189) > >> >>> - locked <0x00000007c0baa518> (a > >> >>> com.mysql.jdbc.util.ReadAheadInputStream) > >> >>> at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:2499) > >> >>> at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2952) > >> >>> at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2941) > >> >>> at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3489) > >> >>> at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1959) > >> >>> at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2113) > >> >>> at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2562) > >> >>> - locked <0x00000007c0baa850> (a java.lang.Object) > >> >>> at > com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1664) > >> >>> - locked <0x00000007c0baa850> (a java.lang.Object) > >> >>> at > com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1583) > >> >>> at > >> >>> > >> >>> > org.hibernate.tool.hbm2ddl.DatabaseExporter.export(DatabaseExporter.java:47) > >> >>> at > >> >>> > org.hibernate.tool.hbm2ddl.SchemaExport.perform(SchemaExport.java:476) > >> >>> at > >> >>> > org.hibernate.tool.hbm2ddl.SchemaExport.execute(SchemaExport.java:430) > >> >>> at > org.hibernate.tool.hbm2ddl.SchemaExport.drop(SchemaExport.java:375) > >> >>> at > org.hibernate.tool.hbm2ddl.SchemaExport.drop(SchemaExport.java:371) > >> >>> at > >> >>> > >> >>> > org.hibernate.internal.SessionFactoryImpl.close(SessionFactoryImpl.java:1069) > >> >>> at > >> >>> > >> >>> > org.hibernate.search.test.util.FullTextSessionBuilder.close(FullTextSessionBuilder.java:149) > >> >>> at > >> >>> > >> >>> > org.hibernate.search.test.util.FullTextSessionBuilder$1.evaluate(FullTextSessionBuilder.java:248) > >> >>> at org.junit.rules.RunRules.evaluate(RunRules.java:20) > >> >>> at org.junit.runners.ParentRunner.run(ParentRunner.java:309) > >> >>> at > >> >>> > >> >>> > org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:264) > >> >>> at > >> >>> > >> >>> > org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:153) > >> >>> at > >> >>> > >> >>> > org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:124) > >> >>> at > >> >>> > >> >>> > org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:200) > >> >>> at > >> >>> > >> >>> > org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:153) > >> >>> at > >> >>> > >> >>> > org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:103) > >> >>> > >> >>> On Gail's suggestion I went looking for database level locks; I > hadn't > >> >>> thought of that as I assumed it would have timed out more > aggressively > >> >>> rather than have me wait for hours. > >> >>> It turns out she was right and the reason for blocking was a simple > >> >>> "count *" query being run as a post-test assertion, which we had > >> >>> forgotten to wrap in an "open transaction & commit" statements > pair. > >> >>> The test assertion would be successful, but apparently it would > hold > >> >>> on the table lock beyond closing the Session and, then fail to drop > >> >>> the database at the teardown of the test. > >> >>> > >> >>> I'm wondering if this is expected, or if there's something in the > new > >> >>> transaction handling code which could be improved? It took me > several > >> >>> hours to figure this out; maybe I'm just not using ORM as > frequently > >> >>> as once :) > >> >>> If it's this critical to have the transaction, maybe it should be > >> >>> mandatory? > >> >>> > >> >>> And as a memo for next time, this is the query to figure out > details > >> >>> about locks on our testing db: > >> >>> > SELECT * FROM pg_locks pl LEFT JOIN pg_stat_activity psa ON > pl.pid > >> >>> = psa.pid where datname = 'testingdb'; > >> >>> > >> >>> Thanks, > >> >>> Sanne > >> >>> _______________________________________________ > >> >>> hibernate-dev mailing list > >> >>> hibernate-dev(a)lists.jboss.org > >> >>> https://lists.jboss.org/mailman/listinfo/hibernate-dev >